U.S. patent number 5,487,644 [Application Number 08/323,589] was granted by the patent office on 1996-01-30 for pump having a single or a plurality of helical blades.
This patent grant is currently assigned to Ishigaki Mechanical Industry Co., Ltd. Invention is credited to Takaharu Honda, Eiichi Ishigaki, Kazumitsu Oura.
United States Patent |
5,487,644 |
Ishigaki , et al. |
January 30, 1996 |
Pump having a single or a plurality of helical blades
Abstract
A vertical pump (1) having a single or plurality of helical
blades (10, 11, 12) mounted on a forward end of a rotary drive
shaft (2) of the pump. The pump is of nonblocked type in which the
helical blade or blades (10, 11, 12) are disposed with superior
balance with respect to the rotary drive shaft (2), and is wide in
flow passage between blade portions of the helical blades. The pump
is particularly suitable for sewage treatment or the like.
Inventors: |
Ishigaki; Eiichi (Kagawa,
JP), Oura; Kazumitsu (Kagawa, JP), Honda;
Takaharu (Kagawa, JP) |
Assignee: |
Ishigaki Mechanical Industry Co.,
Ltd (Tokyo, JP)
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Family
ID: |
27282702 |
Appl.
No.: |
08/323,589 |
Filed: |
October 17, 1994 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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941446 |
Dec 14, 1992 |
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Foreign Application Priority Data
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Feb 13, 1987 [JP] |
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62-19618 |
Aug 31, 1989 [JP] |
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1-102287 |
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Current U.S.
Class: |
415/220;
415/182.1; 415/206; 415/71 |
Current CPC
Class: |
F04D
1/04 (20130101); F04D 29/183 (20130101); F05B
2250/25 (20130101) |
Current International
Class: |
F04D
1/00 (20060101); F04D 1/04 (20060101); F04D
29/18 (20060101); F01D 009/00 () |
Field of
Search: |
;415/182.1,191,201,208.1,211.2,219.1,220,71,206 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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8084 |
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Jul 1957 |
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JP |
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50020 |
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Jan 1974 |
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JP |
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181997 |
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Nov 1982 |
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JP |
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126588 |
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Aug 1988 |
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JP |
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Other References
"Die Pumpen in Meerwasserentsalzungsanlagen nach dem Mehrstufigen
Entspannungsverdampfungs-Verfahren", vol. 113, No. 4, Mar. 1971,
Manfred Lenhard..
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Primary Examiner: Kwon; John T.
Attorney, Agent or Firm: Jones & Askew
Parent Case Text
This is a continuation of application Ser. No. 07/941,446, filed
Dec. 14, 1992, now abandoned.
Claims
We claim:
1. A vertical pump wherein a plurality of blades (10, 11, 12) is
fixedly mounted on a forward end of a rotary drive shaft (2) and
wherein an outer peripheral portion (32) of each of said plurality
of blades (10, 11, 12) is in proximity with an inner surface of a
casing (20), characterized in that:
said casing (20) extending in the direction of said rotary drive
shaft 92) has a bell mouth (24) fixed on a lower end of said casing
(20) and a portion of said casing (20), surrounding said blades
(10, 11, 12), has a configuration bulged in the form of a bowl;
said blades (10, 11, 12) are helical in configuration, and are
arranged with their phases equidistantly shifted respectively about
said rotary drive shaft (2);
each said helical blade has a forward end portion extending
downwardly more than the lower end of said casing (20) and less
than the lower end of said bell mouth (24);
a plurality of twisted guide vanes (14) is arranged at a flow
passage in an upper portion above said helical blades (10, 11, 12)
in said bowl-shaped configuration portion of said casing (20);
and
said bowl-shaped configuration portion of said casing (20), by
which said helical blade (10, 11, 12) and said guide vane (14) are
surrounded, is divided at a location between said blades (10, 11,
12) and said guide vanes (14) and at an intermediate portion of
said guide vanes (14), whereby said casing is formed by three
portions.
2. The vertical pump of claim 1, wherein two helical blades (10,
11) are mounted on said rotary drive shaft (2), said blades being
arranged symmetrically with respect to said shaft with their phases
shifted 180.degree. from each other about said rotary drive shaft
(2).
3. The vertical pump of claim 1, wherein three helical blades (10,
11, 12) are mounted on said rotary drive shaft (2), said blades
being arranged with their phases shifted 120.degree. from each
other about said rotary drive shaft (2).
Description
TECHNICAL FIELD
The present invention relates to a vertical pump having a single or
a plurality of helleal or spiral blades and, more particularly, to
a pump suitable for sewage treatment or the like.
BACKGROUND ART
Conventionally, in a vertical pump, a rotor having a plurality of
blades extending radially in a plane perpendicular to a main
spindle of the pump is arranged at a lower position within a easing
of the pump and is rotated to execute drawing or suction of water
from a lower end of the casing.
However, this vertical pump has the following disadvantages. That
is, since the pump comprises the plurality of blades which are so
spread as to extend radially in the plane perpendicular to the main
spindle of the pump, toward the casing, a passing area of water
stream or flow is limited or narrowed. Particularly, in a case
where sewage is sucked or drawn, cloths and solid matters which may
be contained in the sewage lodge within the pump.
Further, a centrifugal pump is known which is disclosed in Japanese
Patent Laid-Open No. SHO 57-181997, as a pump having a single
helical blade.
However, such a centrifugal pump has the following disadvantage.
That is, since water drawn in a direction of the main spindle of
the pump flows in a direction perpendicular to the main spindle,
solid matters and the like lodge within the pump.
Furthermore, depending upon water pumping environment, there may be
a case where a vertical type non-blocked pump is required.
It is an object of the invention to provide a vertical pump which
is non-blocked and which is large in lift and in discharge quantity
or delivery.
DISCLOSURE OF THE INVENTION
In order to achieve the above-described purpose, in a vertical pump
according to the invention, a single helical blade is fixedly
mounted on a tip of a rotary drive shaft of the pump, an outer
peripheral edge portion of the single helical blade is in proximity
with an inner surface of a casing of the pump, the casing extends
in the direction of the rotary drive shaft, the helical blade is
arranged with superior balance with respect to the rotary drive
shaft, an interval between upper and lower blade portions of the
blade is widened, and a plurality of long twisted guide vanes are
arranged at a flow passage above the blade.
By this arrangement, even if water is water including cloths and
solid matters such as sewage or the like, there is no case where
the water drawn from a lower portion of the casing into between
tile blade portions of the helical blade having the wide flow
passage causes the pump to be clogged. Moreover, since the blade is
contiguous to each other in a helical form so as to be formed into
a single blade extending upwardly, it is possible to raise the
lift. Further, since the blade is arranged with superior balance
with respect to the drive shaft, there is less in case where
harmful oscillation or vibration occurs in the pump. Furthermore,
water flow pumped up helically is adequately and gradually
straightened or uniformed by the plurality of twisted long guide
vanes so that there is less that harmful vibration occurs in the
pump.
In an aspect, the pump is brought to a vertical oblique-flow pump
in which a configuration of the casing at a portion in which the
helical blade and the guide vanes exist is brought to a bowl or pot
type configuration.
In an alternate aspect, in order to further improve the pump
performance, a plurality of helical blades each having the
above-described aspect are arranged with them in shift in phase
with equal intervals each other about the rotary drive shaft of the
pump.
With the above arrangement, volumetric efficiency is raised, and it
is possible to increase the lift. Furthermore, it is possible also
to enlarge the caliber or aperture of the pump so that the
discharge quantity or delivery can increase. Generally, since
enlargement of the aperture of the pump increases the dimension of
the blade so that its weight considerably increases, balance with
respect to the drive shaft of the blade is apt to be deteriorated
by the single helical blade so that harmful vibration is generated
in the pump and the efficiently of the pump is reduced. In the pump
according to an embodiment of the invention, however, since the
plurality of helical blades are arranged, the balance is extremely
improved so that vibration imparted to the pump is extremely
reduced. In a case where there are two helical blades, suction
ports and discharge ports within the casing are located
shaft-symmetrically with respect to the main spindle of the pump.
Accordingly, balance becomes superior. Moreover, also in a case
where there are three helical blades, since the suction ports and
the discharge ports are similarly distributed symmetrically, there
can be produced similar advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view showing a vertical pump
having a single or two or more helical blades, according to the
invention;
FIG. 2 is a partially cross-sectional view of a forward end portion
of the pump illustrated in FIG. 1, showing a case having a single
helical blade;
FIG. 3 is a partially cross-sectional view of a forward end portion
of the pump illustrated in FIG. 1, showing a case having two
helical blades;
FIG. 4 is a bottom view of FIG. 3; and FIG. 5 is a bottom view
showing a pump having three helical blades, according to the
invention.
BEST MODE FOR CARRYING OUT THE INVENTION
A pump having a single or a plurality of helical blades, according
to the invention, will be described below in further detail with
reference to the drawings.
FIG. 1 is a schematic view showing a pump 1 according to the
invention. A hub 8 is fixedly mounted on a forward end of a rotary
drive shaft 2 which is rotated by drive means, for example, a motor
(not shown). At least one helical blade 10 is mounted on the hub
8.
When the drive shaft 2 is rotated, water is drawn from a suction
port 4 of a bell mouth 24 which is arranged below a casing 20 of
the pump 1. The drawn water is straightened or uniformed by a
plurality of twisted guide vanes 14 which are arranged above the
helical blade 10 at a location within the casing 20, and is pumped
up to a tube 18 at an upper portion of the casing 20. It is
required that the guide vanes 14 gradually uniform the water flow
pumped up helically along the helical blade, so as to flow straight
within the tube 18, to eliminate evils such as vibration or the
like to the pump. For this purpose, the guide vanes 14 are twisted
about 270.degree.. Moreover, the twisted guide vanes 14 are
lengthened in order to obtain or produce adequate uniforming of the
flow.
As a result that the guide vanes 14 are lengthened, the casing 20
is lengthened. Accordingly, the casing 20 is divided into
multi-stage portions 21, 22 and 23 at a location between the
helical blade 10 and the guide vanes 14 and at a location at an
intermediate portion of each of the guide vanes 14, for the purpose
of assembling and maintenance of the pump.
FIG. 2 is a partially cross-sectional side elevational view showing
a principal portion of a lower end section of the pump illustrated
in FIG. 1, showing the pump 1 having a single helical blade 10.
Description will be made to the helical blade 10. The blade 10 has
a configuration thereof wound helically about the rotary drive
shaft 2 through an adequate angle. The blade 10 is mounted on the
hub 8 at a proximal end portion 30 of the blade 10. An outer
peripheral edge portion 32 opposite to the proximal end portion 30
is in proximity with an inner surface of the casing 20. The hub 8
and the helical blade 10 may be formed integrally as a casting. A
forward end potion 33 of the helical blade 10 extends downwardly
more than a forward end portion 9 of the hub 8, whereby the wide
suction port 4 is formed. The end portion 33 of the helical blade
10 extends downwardly more than the lower end of the casing 20 but
less than the lower end of the bell-shaped mouth 24, as shown in
FIG. 2. An interval between the upper and lower blade portions
serving as a flow passage is adequately widened so as to allow
cloths and solid matters included in sewage and the like pumped up,
to pass.
When the drive shaft 2 is rotated, the pumped-up water is drawn
from the suction port 4, flows toward a discharge port 5 through
gaps between the blade portions, and is uniformed by the plurality
of twisted guide vanes 14 each of which is long in length, as
described previously.
The helical blade 10 is so formed that weight balance is superior
with respect to the drive shaft 2. Further, the blade exists
continuously over the predetermined length in the direction along
the drive shaft, different from the conventional pump which has the
plurality of blades only in a single plane perpendicular to the
drive shaft 2. Thus, it is possible to increase the lift.
In the figure, the vertical oblique-flow pump 1 is shown whose
configuration is such that a portion of the vertical oblique-flow
pump 1 including the helical blade 10 and the guide vanes 14 of
which casing 20 is swelled or bulged into the form of a bowl- or
pot-like configuration. However, the vertical pump 1 may be a
vertical axial-flow pump having no bowl portion and having a
configuration in which the casing 20 is straight as a whole.
FIG. 3 is a partially cross-sectional side elevational view showing
a principal portion of a lower end section of the pump 1
illustrated in FIG. 1. FIG. 4 is a bottom view of FIG. 3, showing
the pump 1 having a pair or helical blades 10 and 11.
Each of the helical blades 10 and 11 is manufactured such that a
sheet material is processed into a helical configuration. As will
be understood from FIG. 4, the blades 10 and 11 are wound helically
through 360.degree. about the rotary drive shaft 2 of the pump 1
such that their phases shift 180.degree. from each other so as to
be symmetrical with respect to the shaft. The blades 10 and 11 are
mounted on the hub 8 at their respective proximal end portions 30
and 30. Outer peripheral edge portions 32 and 32 opposite
respectively to the proximal end portions 30 and 30 are in
proximity with the inner surface of the casing 20. The forward end
portions 33 and 33 of the respective helical blades 10 and 11
extend downwardly from the forward end portion 9 of the hub 8, to
thereby form wide suction ports 4 and 4. An interval of the
alternate blade portions of the two blades 10 and 11 serving as a
flow passage is adequately widened so that cloths and solid matters
included in the sewage and the like pumped up can pass.
When the drive shaft 2 is rotated, the pumped water is drawn
simultaneously from the two suction ports 4 and 4 which are located
in symmetrical relation to each other with respect to the shaft,
passes through gaps between the blade portions, generates a flow in
a single helical direction, flows into the two discharge ports 5
and 5 which are located in symmetrical relation to each other with
reference to the shaft, and is uniformed by the plurality of
twisted guide vanes 14 which are long in length, as described
previously.
As described above, in a case where two helical blades 10 and 11
are provided in this manner, the blades are arranged symmetrically
with respect to the shaft, and the suction ports and the discharge
ports are also arranged in symmetrical relation to each other.
Thus, the pump is brought to a pump extremely superior in balance.
Further, in a case of a single helical blade, assuming that a
single plane extending perpendicularly to the drive shaft 2 is
considered, energy is given to the water at a single eccentric
location, and energy cannot be applied equally, so that volumetric
efficiency is bad. Generally, the delivery or discharge quantity of
the pump is in proportion to the caliber or aperture of the pump.
In a case of a single helical blade, however, it is impossible to
cover the whole volume of the water for the reason discussed above.
Accordingly, if the aperture of the pump increases, the discharge
quantity does not increase in proportion thereto. On the other
hand, in a case of a pump having two helical blades, energy is
given to water at two locations symmetrical to each other with
respect to the shaft, simultaneously in every or all planes
extending perpendicularly to the drive shaft 2 so that the
volumetric efficiency becomes superior. As a result, it is possible
to raise the lift and enlarge the aperture of the pump in order to
increase the discharge quantity. Tests have been conducted with
respect to a vertical oblique-flow pump illustrated in FIG. 3. As a
result, it has been known that efficiency is superior 4-5% as
compared with the conventional oblique-flow pump.
FIG. 5 shows a case where three identical helical blades 10, 11 and
12 are mounted on the hub 8 in place of the two helical blades of
the pump illustrated in FIG. 3, with phases shifted 120.degree.
from each other. Also in this case, the blades as well as the
suction ports and the discharge ports are dispersed equally
similarly to the pump illustrated in FIG. 3, so that the pump is
brought to a pump superior in balance and superior in volumetric
efficiency.
It is preferable that the number of provided helical blades is
decided depending upon a condition in which the dimension of the
casing 20 of the pump 1 and the flow of the fluid within the pump
are brought into uniformity, and other design conditions. In this
connection, FIG. 3 shows the vertical oblique-flow pump 1 in which
a portion including the helical blades 10 and 11 and the guide
vanes 14 of the casing 20 are bulged in the form of a bowl or pot.
However, the pump may be brought to a vertical axial-flow pump in
which there is no bowl portion and which has a configuration in
which the entire casing 20 is straight.
INDUSTRIAL APPLICABILITY
As described above, since the pump having a single or a plurality
of helical blades, according to the invention, can be made large in
lift and large in discharge quantity, there are produced advantages
that a conventional relay station for pumping up arranged in a case
where the lift is small can be omitted, and the like. Thus, it is
possible to utilize the pump widely in various industries.
Moreover, since the flow passage within the pump is relatively wide
and is a single direction in the direction of the drive shaft,
things or objects do not lodge. Thus, the pump can also be utilized
for pumping up of sewage or the like containing articles such as a
block of cloth or paper which tends to block conventional
pumps.
* * * * *